There is known a game machine in which a virtual camera is installed in a virtual three dimension space and a picture obtained by viewing the virtual three dimension space from the virtual camera is displayed as a game image. In such a game machine, generally, the game player can change the position and/or posture of the virtual camera by operating a direction key, an operation stick, and so forth, for example.    Patent Document 1: Japanese Patent Laid-open Publication No. Hei 7-116343